About one in every 10 people who died last week nationwide succumbed to influenza in a season so fierce it is on track to be one of the worst flu epidemics on record, a top federal health official said Friday.
“We may be on track to break several records,” Dr. Anne Schuchat, acting director of the Centers for Disease Control and Prevention said in a telephone news briefing.
Within the past seven days, 10 more children have died across the country, bringing the season’s total to 63, Schuchat said.
In New York state, four children have died as a result of influenza so far — three of them in New York City.
New York City Health Department officials on Friday confirmed the flu-related death of the third child, after earlier in the week verifying that two children had died of the respiratory infection.
The State Health Department had last month confirmed the first pediatric death in New York this season. That child was identified only as having been a resident of the downstate region.
It was not immediately clear if all of the New York City pediatric deaths were included the latest CDC figures.
Pediatric deaths are considered a bellwether of flu season severity.
A steady rise in childhood deaths suggests a potent circulating strain of the primary influenza A virus. But while the overall number of flu cases reported to date nationwide — pediatric and adult — align with those of the 2009 swine flu scare, the current epidemic is not caused by a novel virus as was the case nine years ago. Also, the current outbreak is not a pandemic, a designation that was given to the 2009 outbreak that circulated around the globe.
In addition, influenza is causing a record number of people between the ages of 50 and 64 to be hospitalized for the respiratory illness, Schuchat said, and federal health officials are aware of hospitalized patients being affected simultaneously by two different flu strains.
Doctors are reporting that some patients have been infected with H3N2, the primary A strain of the flu, along with a B strain. In other instances, patients have been infected with H3N2 and later developed a second bout of the flu caused by influenza B.
Schuchat said hospitalizations also have increased for people who have developed bacterial pneumonia as a consequence of the flu. She recommended that people 65 and older see a health care provider for a pneumococcal vaccination, a shot that protects against several bacterial strains of pneumonia.
“The flu is not just the sniffles and cough,” Schuchat said. As she did in a briefing a week ago, Schuchat recommended flu shots for those who have not yet received one.
CDC data show 48 of the 50 states reporting high influenza-like illness. This is the 11th week of intense flu. The illnesses have begun to decline in Oregon and Hawaii, Schuchat said.
“Flu is incredibly difficult to predict, and we don’t know if we have hit the peak yet,” she said, noting that 59.9 hospitalizations per 100,000 people in the population have been for the flu so far this year.
The CDC began tracking hospitalizations in 2010. In the most recent severe flu season, which was 2014-15, there were 35.1 flu hospitalizations per 100,000 people, she said.
Federal health officials have not yet fully studied the effectiveness of this year’s vaccine, but Schuchat said data from Canada demonstrate that the current vaccine is not as effective against H3N2 as health officials would have hoped.
However, the vaccine does help those who get the shot build stronger immunity against the B strain, Schuchat said, citing the Canadian research.
Flu pandemics and epidemics
Flu pandemics are caused by novel influenza viruses that have never infected human populations. Epidemics are serious and are caused by genetic variations of common flu viral strains that circulate seasonally.
- 1918 (pandemic) — Deadliest flu outbreak ever. Sometimes called Spanish Flu. The strain is believed to have been of bird origin. It infected an estimated 500 million people globally and killed between 50 million and 100 million worldwide. More than 600,000 people died in the United States.
- 1957 (pandemic) — The Asian Flu initially was centered in China and caused by a flu strain that jumped from ducks and combined with a flu virus already circulating in human populations. Thedeath toll in the United States was nearly 70,000.
- 1968 (pandemic) — Hong Kong Flu was caused by a virus in which genes from several flu subtypes recombined to create a novel pathogen that never had circulated among humans. Nearly 35,000 people in the United States died.
- 2003-04 (epidemic) — Nationwide outbreak caused by an H3N2 virus known as A/Fujian. In the United States, 153 children died, prompting the Centers for Disease Control and Prevention to urge pediatric flu vaccinations in subsequent years. Adult deaths exceeded the epidemic threshold.
- 2009-10 (pandemic) — Swine Flu was caused by an A strain virus called H1N1 that originated in pigs. The CDC estimates that 12,000 people, including 348 children, died in the United States.
- 2013-14 (epidemic) — Nationwide outbreak spawned by an H3N2 virus. An estimated 96 children died nationally. The CDC indicated that adult deaths exceeded the epidemic threshold.
Sources: Centers for Disease Control and Prevention; Department of Health and Human Services, http://www.pandemicflu.gov/general/historicaloverview.html